High Entropy TPS Materials

Hypersonic aerial vehicles have tailored aerodynamic shapes with sharp leading edges to maximize performance. When a vehicle is travelling through the atmosphere at hypersonic speeds of Mach 5 or higher, it encounters intense friction with the surrounding air. The nose cone and the leading edges of the flight vehicle will experience extremely high temperatures from 3000°F to 5000°F. Ultra-High Temperature Ceramics (UHTCs) have extremely high melting points and are often considered hypersonic structures.  However, single phase UHTCs lack the proper mechanical and oxidation properties. Increasing material entropy has been shown to be a successful approach in metallic alloys to improve high temperature properties. High Entropy (HE) metallic alloys are achieved by combining 5 or more elements (in roughly equal percentages). To produce the next jump in TPS materials, our Phase I team will develop High Entropy Ceramics (HECs).  In the Phase I, we will develop HECs with extreme thermal/mechanical stability.